Field of Technology
The present disclosure relates to a flexible organic light emitting diode display panel, and more particularly, to a flexible organic light emitting diode display panel capable of minimizing peeling of an organic material layer and an encapsulation layer which may occur when a substrate is bent.
Description of the Related Art
An organic light emitting diode (OLED) display is a self-light emitting display panel that does not need a separate light source unlike a liquid crystal display (LCD) panel. Thus, the organic light emitting diode display panel can be manufactured into a lightweight and thin form. Further, the organic light emitting diode display panel is advantageous in terms of power consumption since it is driven with a low voltage. Also, the organic light emitting diode display panel has excellent color expression ability, a high response speed, a wide viewing angle, and a high contrast ratio (CR). Therefore, the organic light emitting diode display panel has been researched as a next-generation display.
Further, since the organic light emitting diode display panel does not need a separate light source, it is advantageous for curved and flexible display panels.
In the organic light emitting diode display panel, a pixel electrode connected with a thin film transistor, an organic light emitting layer, and a common electrode are formed on a substrate including the thin film transistor. The organic light emitting diode display panel is driven by emitting the organic light emitting layer in response to a driving signal of the thin film transistor.
The organic light emitting layer emits light when an electron and a hole injected from the pixel electrode and the common electrode meet in the organic light emitting layer and form an exciton.
Since the organic light emitting layer is sensitive particularly to moisture and oxygen, an encapsulation layer including one or more layers is formed on an organic light emitting diode in order to suppress permeation of moisture and oxygen.
In order to seal the organic light emitting diode, a thin film encapsulation technique of alternately laminating an inorganic material layer and an organic material layer is used.
As an inorganic material for a thin film encapsulation, an oxide layer such as aluminum oxide (AlOx) capable of having an excellent barrier property with small thickness has been mainly used. In particular, as the thickness of the thin film encapsulation is decreased, the flexibility of the organic light emitting diode display panel is improved. Therefore, it is advantageous in using the oxide layer as the inorganic material layer for thin film encapsulation in order to realize a flexible organic light emitting diode display panel.
However, the organic light emitting layer tends to have lower adhesion than other components constituting the organic light emitting diode display panel. Thus, peeling of the flexible organic light emitting diode display panel may occur when the display panel is bent.
Further, peeling of the encapsulation layer may occur when the display panel is bent.